Method and apparatus for the prevention of souping in diesel engines



H. U. WISNIOWSKI METHOD AND APPARATUS FOR THE PREVENTION Jan. 3, 1967vOF SOUPING IN DIESEL ENGINES Filed July 22, 1964 HEA/ky u/lsAl/awskd 8,

v vm rm A cnv United States Patent This invention relates to a methodand apparatus for the prevention of souping in diesel engines.

During idling of diesel engines for long periods of time, a phenomenonknown as souping occurs. This souping is evidenced by the appearance ofblack sludge which between the disc and the top of the piston. The sprayholes of the fuel injector 7 inject a spray 13 of fuel into the cavity.These spray holes 12 are directed outwardly and downwardly. It has beenfound that best results in preventing souping are obtained when the fuelsprays impinge partially on the disc 1.

The discs used should be made of high temperatureresistant metal. Theymust be capable of withstanding the temperatures of up to 1100" C.encountered in the combustion chambers. Tests have shown that discs madeof Nichrome or Inconel are quite suitable.

The following experimental results were obtained on a l2-cylinderlocomotive diesel engine. An anti-souping disc was placed in the No. 1cylinder as indicated.

First cylinder Cylinder No. 1 Total Anti-souping device in No. 1 Fuelstarted to soup started to soup Hours of cylinder after after- IdlingFlat annular Pembina Crude Oil 7 75 hrs 48.5 hrs 51 do 7 hrs 53 hrs 66do 6.75 hrs 62.75 hrs 73 Standard Diesel Fuel 22.25 hrs 100.25 hrs 115comes out from the exhaust system of the engine. Souping is mostpronounced in locomotive diesel engines which are left idling for longperiods of time. Diesel engines for other services are normally not leftidling long enough to show souping.

Souping is manifested externally by a bluish-grey smoke of a fog typeissuing from the exhaust. If the engine is examined, unburned orpartially unburned fuel will be found in the cylinders and in theexhaust system.

Souping has occurred in locomotive service with standard diesel fuel butwhen crude oils were tested as substitute fuels, the souping phenomenonwas found to be much aggravated. In its heavy form souping istroublesome and greatly increases the fire danger of the installationand surroundings. It is also suspected that it accelerates thedeterioration of the lubricating oil and increases the wear of theengine.

It is an object of the present invention to provide a method ofeliminating or reducing the occurrence of souping in diesel enginesespecially those on locomotive service.

It is another object of the invention to provide a means of reducingsouping which is reasonably inexpensive, easily adaptable to presentengines, and which is fixed in position and, therefore, not subject todynamic forces which might tend to destroy it.

In drawings which illustrate embodiments of the invention,

FIGURE 1 shows the preferred form of the invention attached to thecylinder head of a diesel engine,

FIGURE 2 shows a cross section of the device of FIG- UREl.

Referring to FIGURE 1 a cylinder head 4 of a diesel engine with inletand exhaust ports 5 and valves 4A is shown. A flat circular metallicdisc 1 having a central aperture 6 is fixed to the cylinder head andpositioned from it by means of legs 2. Studs 3, which screw into holesdrilled in the head, hold the disc securely in place.

FIGURE 2 shows a cross-section of a cylinder head 4 and a piston 11.Disc 1 should be located away from the surface of cylinder head 4 sothat the temperature of the disc will be higher (closer to that of thegas in the cavity) than that of the cylinder head itself. For mechanicalreasons sufficient clearance should be allowed It can be readily seenfrom these results that the use of the anti-souping devices greatlyincreases the length of time that a diesel engine can be idled beforesouping becomes evident. This improvement is obtained even with heavycrude oils and by using the devices, one of the drawbacks to using thistype of fuel is almost eliminated.

The above results were found to be reproducible and it can be expectedwith reasonable probability that provided the injectors are in goodcondition, the start of visible souping with the anti-souping discs willnot occur before 50 hours of idling on crude oils. In the case ofstandard diesel fuels the souping-free time with the discs is at leasthours.

Investigations conducted on the test engine and combustion rig showedthat souping is caused to a great extent by the contact of injected fuelwith the relatively cold Walls of the combustion chambers resulting inpartial burning or no burning of a part of this fuel.

The anti-souping discs when placed in the combustion chamber are heatedby combustion gases to the temperature much above the temperature of thewalls of the chamber. The injected sprays of fuel either strike the hotdiscs or pass close to it by which they .are heated and burnt beforethey reach the cold walls of the combustion chamber. In this Way, thesouping problem is greatly alleviated.

What is claimed is:

In a diesel engine of the type having a cylinder, a piston in thecylinder, a cylinder head forming a combustion chamber above saidpiston, and a fuel nozzle located in said head, constructed to dischargeseparate conical spray patterns at widely divergent angles generallyradially from the nozzle and through said combustion chamber formedbetween the crown of said piston and said cylinder head; the improvementcomprising a generally fiat disk located in said combustion chamberarranged in a plane transverse to an axis bisecting the divergent angleof the spray pattern, means for supporting said disk spaced from thepiston and cylinder head with the central portion of said disk exposedonly to the gases in said chamber and with only the periphery of saiddisk disposed to intercept a portion of the conical sprays from saidnozzle which approach the adjacent head of the piston, said means pro- Jviding suflicient spacing to form a barrier to heat transfer from thedisk to maintain disk temperature above ignition temperature at engineidle speeds.

References Cited by the Examiner UNITED STATES PATENTS 535,837 3/1895Lorenz 123-30.3

1,213,911 1/1917 Schmid 12330.3

1,515,496 11/1924 Laeubli 123-32 1,781,327 11/1930 Goinard 23--30.3

2,071,062 2/1937 Cummins 12332 2,761,431 9/1956 Na llinger 123-32 IFOREIGN PATENTS 589,381 2/1925 France. 905,902 3/1954 Germany. 958,7892/1957 Germany.

MARK NEWMAN, Primary Examiner.

m RICHARD B. WILKINSON, Examiner.

L. M. GOODRIDGE, Assistant Examiner.

